HSEES Contacts

Annual Report 1996

Historical Document

This document is provided by the Agency for Toxic Substances and Disease Registry (ATSDR)
ONLY as an historical reference for the public health community. It is no longer being maintained and the data
it contains may no longer be current and/or accurate.

In 1980, Congress created the Agency for Toxic Substances and
Disease Registry (ATSDR) to implement health-related sections
of laws that protect the public from hazardous wastes and
environmental spills of hazardous substances. The Comprehensive
Environmental Response, Compensation, and Liability Act of 1980
(CERCLA), commonly known as the "Superfund" Act, designated
ATSDR as the lead agency within the Public Health Service to help
prevent or reduce further exposure to hazardous substances and
the adverse health effects that result from such exposures, and
also to expand the knowledge base about such effects.

This publication reports the results and findings of a health
study, registry, or other health-related activity supported by
ATSDR in accordance with its legislative mandate described
above.

Mention of the name of any company or product does not constitute endorsement by the Agency for Toxic Substances and Disease Registry, the Public Health Service, or the U.S.
Department of Health and Human Services.

Since 1990, the Agency for Toxic Substances and
Disease Registry (ATSDR) has maintained an active, state-based
Hazardous Substances Emergency Events Surveillance (HSEES) system
to describe the public health consequences associated with the
release of hazardous substances. Five state health departments
participated in the pilot phase of the surveillance system and
began data collection on January 1, 1990. Since 1995, the number
of participating state health departments has remained at 14.
This report summarizes the characteristics of events reported to
the surveillance system from January 1, 1996, through December
31, 1996.

Information on acute hazardous substances emergency
events was collected on data collection forms designed by ATSDR.
The types of data collected included general information on the
event, substance(s) released, victims, injuries, and evacuations.
Estimates have been made of the number of people at risk of
exposure by a particular event.

Several data sources were used to obtain the
maximum amount of information about these events. These sources
included, but were not limited to, records or oral reports of
state environmental protection agencies, police and fire
departments, and hospitals. The data obtained were computerized
using an ATSDR-provided data entry system and were sent to ATSDR
quarterly.

The 14 states reported a total of 5,502 events for
1996; 79% of the events occurred at fixed facilities and 21% were
transportation related. In 96% of the events, only a single
substance was released. The most commonly reported categories
of substances were "Volatile organic compounds"; "Acids";
"Ammonia"; "Pesticides"; "Other inorganic substances"; and the
category designated "Other," which included mixtures of
substances, as well as substances that were not mixtures but
could not be placed in one of the other nine categories. During
this reporting period, 390 events (approximately 7% of all
events) resulted in a total of 1,620 victims. The most
frequently reported injuries sustained by victims were
respiratory irritation, eye irritation, nausea or vomiting, and
headache. There were a total of 33 deaths in all events, and 543
events required evacuations.

The findings regarding the distribution of the
types of events, the numbers of events with victims and
evacuations, and the injuries reported have, overall, been
consistent over the years.

INTRODUCTION

Since 1990, the Agency for Toxic Substances and
Disease Registry (ATSDR) has maintained an active, state-based
Hazardous Substances Emergency Events Surveillance (HSEES)
system to describe the public health consequences associated with
the release of hazardous substances. The decision to initiate a
surveillance system of this type was based on a 1988 study on
the reporting of hazardous substances releases to three national
databases: the National Response Center Data Base, the
Hazardous Materials Information System (HMIS), and the Acute
Hazardous Events Data Base (1). Review of the national
databases indicated that they were limited because many events
were missed through incomplete reporting (for example, HMIS
does not include intrastate carrier or fixed-facility events).
Other missing information included demographic information about
victims, the types of injuries received, and the number of people
evacuated. As a result of this review, ATSDR implemented the
HSEES system to describe the public health consequences
associated with the release of hazardous substances. The
surveillance system has four goals:

To describe the distribution and
characteristics of hazardous substances emergencies.

To describe the morbidity and
mortality experienced by employees, responders, and the general
public as a result of hazardous substances releases.

To identify risk factors associated
with the morbidity and mortality.

To identify strategies that might
reduce future morbidity and mortality resulting from the release
of hazardous substances.

This report summarizes the characteristics of
hazardous substances releases and the associated public health
consequences reported to the surveillance system from January 1,
1996, through December 31, 1996.

METHODS

In 1996, 14 state health departments collected data
for HSEES. Information was collected on standardized data
collection forms. The types of information collected on data
collection forms included information on the event, substance(s)
released, victims, injuries, and evacuations.

Various data
sources were used to obtain information about these events.
These sources included, but were not limited to, records and oral
reports of state environmental protection agencies, police and
fire departments, and hospitals. Census data were used to
estimate populations residing in the vicinity of the vents. All
of the data were computerized using an ATSDR-provided data entry
system and were sent to ATSDR quarterly.

Hazardous substances emergency events were defined
as uncontrolled or illegal releases or threatened releases of
hazardous substances or the hazardous by-products of substances.
Not included were events involving petroleum products
exclusively. Events were included when the amount of substance
that was released, or that might have been released, needed (or
would have needed) to be removed, cleaned up, or neutralized
according to federal, state, or local law; or when there was only
a threatened release of a substance, but this threat led to an
action (for example, evacuation) that could have affected the
health of employees, responders, or the general public. Victims
were defined as those people who suffered at least one injury or
died as a consequence of the event. In counting injuries,
victims could have been counted more than once if they had more
than one injury. Events were defined as transportation related
when they occurred during surface, air, or water transport of
hazardous substances. Fixed-facility events were defined as
events occurring at industrial sites, schools, farms, or any
other type of facility. For the analyses, the substances
released were categorized into 10 groups.

RESULTS

A total of 5,502 events were reported in 1996 to the HSEES system
by the 14 participating state health departments. Seventy-nine percent of the
events occurred at fixed facilities and 21% were transportation related (Table 1). About 2% of all events were threatened
releases.

Factors contributing to fixed-facility events were
also reported. In the 4,343 fixed-facility events, approximately
62% involved equipment failure as a factor contributing to the
occurrence of the event. Sixteen percent of fixed-facility
events were reported as involving operator error.

Table 1 - Number of events meeting the surveillance definition,
reported by state and type of event, Hazardous Substances Emergency Events Surveillance,
January 1 - December 31, 1996.

STATE REPORTING EVENT

FIXED FACILITY EVENTS

%

TRANS- PORTATION EVENTS

%

TOTAL NUMBER OF EVENTS

Alabama

166

(81.8)

37

(18.2)

203

Colorado

101

(31.2)

223

(68.8)

324

Iowa

203

(68.1)

95

(31.9)

298

Minnesota

224

(74.4)

77

(25.6)

301

Mississippi

70

(59.8)

47

(40.2)

117

Missouri

109

(68.1)

51

(31.9)

160

New Hampshire

30

(78.9)

8

(21.1)

38

New York

379

(89.2)

46

(10.8)

425

North Carolina

128

(74.0)

45

(26.0)

173

Oregon

135

(64.0)

76

(36.0)

211

Rhode Island

30

(83.3)

6

(16.7)

36

Texas

2,265

(91.0)

223

(9.0)

2,488

Washington

291

(73.5)

105

(26.5)

396

Wisconsin

212

(63.9)

120

(36.1)

332

Total

4,343

(78.9)

1,159

(21.1)

5,502

Ninety-six percent of the events involved the release of only one
substance. Two substances were released in approximately 3% of the events (Table
2).

Most releases were either liquid spills (55%) or
air emissions (39%). The remaining releases were the result of
fires (3%) or other types of releases (3%).

Events occurred primarily from 6 AM through 11:59
AM (38%) and from 12 noon through 5:59 PM (32%). Approximately
18% of events occurred at some time during the weekend.

Of the 10 categories into which HSEES substances were grouped, "Volatile
organic compounds" (VOCs) (19%), "Other inorganic substances" (25%), "Ammonia"
(9%), "Acids" (7%), and "Other" substances (28%) were most commonly released
in fixed-facility events (Table 3). The
category "Other" consisted of mixtures of substances from different categories,
as well as substances that were not mixtures but could not be placed in one
of the other nine substance categories. The category "Other inorganic substances"
comprised all inorganic substances except for acids, bases, ammonia, and chlorine.
In transportation-related events, the categories "Pesticides" (15%), "Other
inorganic substances" (12%), "Volatile organic compounds" (12%), "Acids" (12%),
and "Other" substances (33%) were most frequently reported.

Table 4 shows the distribution
of the number of victims by the type of event. A total of 1,620 victims were
involved in 390 events (approximately 7% of all events). Approximately 46% of
the events with victims involved only one victim; about 68% of the events involved
one or two victims. Fixed-facility events accounted for the majority (82%) of
victims.

The substance categories with the most events did not necessarily
have the most victims (Table 5). For
instance, 1,016 events involved VOCs, but only 40 (4%) of these events involved
victims. Although chlorine accounted for only 114 (2%) events, nearly 30% of
chlorine events resulted in victims, indicating its greater potential for harm.

The population groups most often injured were employees (51%) and
the general public (30%) (Figure 1) and, overall, a higher proportion
of responders and the general public were injured in transportation events than
in fixed-facility events.

The types of injuries sustained by victims are shown in Table
6 and in Figure 3. The victims sustained a total of
2,769 injuries. Some victims experienced more than one injury. The most commonly
reported injuries in fixed-facility events were respiratory irritation (40%),
eye irritation (16%), nausea or vomiting (13%), and headache (10%). In transportation-related
events, respiratory irritation (28%), trauma (20%), nausea or vomiting (14%),
and dizziness or other central nervous system (CNS) symptoms (10%) were most
frequently reported. Trauma was more often reported in transportation-related
events than in fixed-facility events. The trauma might have been caused by the
sequence of events (for example, a motor vehicle accident) leading to the release
of a hazardous substance and not necessarily by exposure to the hazardous substance
itself.

The most frequently reported injuries by population
group were also evaluated. Among students, employees, and the

Table 2 - Distribution of the number of substances released,
by type of event, Hazardous Substances Emergency Events Surveillance, January
1 - December 31, 1996.

NUMBER OF SUBSTANCES
RELEASED

FIXED FACILITY EVENTS

FIXED FACILITY SUBSTANCES

TRANS- PORTATION EVENTS

>

TRANS- PORTATION SUBSTANCES

TOTAL NUMBEROFEVENTS

TOTAL NUMBER OF
SUBSTANCES

1

4,206

4,206

1,078

1,078

5,284

5,284

2

90

180

55

110

145

290

3

30

90

16

48

46

138

4

5

20

7

28

12

48

5

5

25

1

5

6

30

6 or more

7

82

2

15

9

97

Total

4,343

4,603

1,159

1,284

5,502

5,887

Table 3 - Distribution of the number of substances released,
by substance category and type of event, Hazardous Substances Emergency Events
Surveillance, January 1 - December 31, 1996.

SUBSTANCE CATEGORY

NUMBER OF FIXED FACILITY SUBSTANCES

%

NUMBER OF TRANS- PORTATION SUBSTANCES

%

TOTAL NUMBER OF SUBSTANCES

%

Acids

324

(7.0)

156

(12.1)

480

(8.2)

Ammonia

393

(8.5)

51

(4.0)

444

(7.5)

Bases

147

(3.2)

94

(7.3)

241

(4.1)

Chlorine

109

(2.4)

5

(0.4)

114

(1.9)

Other inorganic substances

1,137

(24.7)

154

(12.0)

1,291

(21.9)

Paints and dyes

62

(1.4)

52

(4.0)

114

(1.9)

Pesticides

171

(3.7)

194

(15.1)

365

(6.2)

Polychlorinated biphenyls

112

(2.4)

6

(0.5)

118

(2.0)

Volatile organic compounds

861

(18.7)

155

(12.1)

1,016

(17.3)

Other

1,287

(28.0)

417

(32.5)

1,704

(29.0)

Total

4,603

(100.0)

1,284

(100.0)

5,887

(100.0)

Table 4 - Distribution of the number of victims by type of event,
Hazardous Substances Emergency Events Surveillance, January 1 - December 31,
1996.

NUMBER OF VICTIMS

FIXED FACILITY EVENTS

FIXED FACILITY VICTIMS

TRANS- PORTATION EVENTS

TRANS- PORTATION VICTIMS

TOTAL NUMBER OF EVENTS

TOTAL NUMBER OF VICTIMS

1

108

108

73

73

181

181

2

63

126

22

44

85

170

3

28

84

3

9

31

93

4

20

80

1

4

21

84

5

8

40

3

15

11

55

6 or more

48

886

13

151

61

1,037

Total

275

1,324

115

296

390

1,620

Table 5 - Number of substances released in all events and events
with victims, by substance category, Hazardous Substances Emergency Events Surveillance,
January 1 - December 31, 1996.

SUBSTANCE CATEGORY

TOTAL NUMBER OF RELEASES

%

NUMBER OF RELEASES WITH VICTIMS

%

PERCENT OF RELEASES WITH VICTIMS*

Acids

480

(8.2)

65

(13.5)

13.5

Ammonia

444

(7.5)

47

(9.8)

10.6

Bases

241

(4.1)

20

(4.2)

8.3

Chlorine

114

(1.9)

34

(7.1)

29.8

Other inorganic substances

1,291

(22.0)

90

(18.8)

7.0

Paints and dyes

114

(1.9)

6

(1.2)

5.3

Pesticides

365

(6.2)

48

(10.0)

13.2

Polychlorinated biphenyls

118

(2.0)

1

(0.2)

0.8

Volatile organic compounds

1,016

(17.3)

40

(8.3)

3.9

Other

1,704

(28.9)

129

(26.9)

7.6

*Percent of releases that resulted in personal
injury within the substance category calculated by: Percent of
releases with victims = 100 X (Number of releases with victims) /
(Total number of releases)

The number of injuries is greater than the number
of victims, because a victim could have had more than one
injury.
* Central nervous system symptoms or signs.

general public, the most commonly reported injuries
were respiratory irritation, eye irritation, and nausea or
vomiting. Among responders, respiratory irritation, nausea or
vomiting, and dizziness or other central nervous system injuries
were most often reported.

The sex was known for 90% of victims; 65% were
male and 35% were female. Among the population subgroups, more
of the responders (89%) and employees (66%) were male. The
mean age of the victims was about 32 years, with a range from
1 to 86 years. Most victims (66%) were reported to have been
transported to and treated at a hospital, but not admitted.
Fourteen percent were treated at the scene with first aid; 8%
were admitted to a hospital; 4% were transported to hospital for
observation; 4% of victims experienced injuries within 24 hours
that were reported by an official (for example, personnel with
the fire departments, police, or poison control center); 2% were
seen by a private physician within 24 hours; and 2% died.

Among victims, 65% of employees and 45% of
responders did not wear any personal protective equipment. Those
employees who did wear personal protective equipment most
frequently wore a form of eye protection (29%) or level "D"
protection (13%). The personal protective equipment most
frequently worn by first responders was firefighter turnout gear
(38%), level "A" protection (3%), and gloves (3%).

A total of 33 persons died as the result of events; 8 died in 1
event, 3 in 1 event, 2 in each of 3 events; and 1 in each of 16 separate events.
Seventeen of the thirty-three deaths occurred in fixed-facility events and 16
occurred in transportation-related events. Of those who died, all were male;
31 were employees, and 2 were members of the general public. There were no deaths
among responders. Twenty-six sustained traumatic injuries, of which 14 occurred
as a result of transportation events and 12 as a result of fixed-facility vents,
respiratory irritation, chemical or thermal burns, and a cardiac arrest were
the reported injuries sustained by other victims who died.

It was very unusual to have 8 persons die in one
event. These people were employees who wore level D protection
equipment and sustained traumatic injuries in a fixed-facility
event. The two members of the general public who died received
fatal traumatic injuries in separate events one at a
fixed-facility and the other in a transportation-related
event.

The types of contingency or preparedness plans
varied among events, with approximately 39% involving the use of
a company's operating procedures. Thirty-five percent of events
were reported as following an incident-specific ad hoc plan, and
19% involved the use of a HazMat or response team's standard
operating procedures.

Evacuations were ordered in 543 events. Sixty-five
percent of the evacuations were of a building or the affected
part of a building. Fourteen percent were based on a defined
circular area around an event, 18% were based on actual or
anticipated downwind dispersion, and 3% were reported as having
been ordered without criteria. The median number of people
evacuated was 25, with a range of from 0 to 2,200 persons. In
43 events, in-place sheltering was ordered, and instructions
regarding precautions to take during in-place sheltering were
provided in 30 of these events.

SUBSTANCE NAME STANDARDIZATION PROJECT

In 1996, ATSDR began the process of standardizing
the names of substances in the HSEES database. This process,
which has continued into the 1997 data collection year, was
initiated so ATSDR could more effectively perform analyses on
specific substances reported to the database. Although the HSEES
computerized data entry system includes a pick-list of
substances, often there was a need for state coordinators to
manually enter a substance name in a 37-character free text
substance identification field. This often resulted in a great
amount of time being consumed when analyzing substances reported
to the database.

More than 6,000 names of substances reported to the
HSEES system or on the HSEES pick-list since 1990 were reviewed
for spelling accuracy and appropriateness of the substance name.
A mapping system was then created to relate the reported
substance name to a standard substance name which in turn would
be associated with the appropriate HSEES substance category.
Standard substance names adopted by the American Conference of
Governmental Industrial Hygienists (ACGIH) and the Department of
Transportation (DOT) were used to generate standard HSEES
names.

The components of substances reported to the HSEES as mixtures were
arranged in alphabetical order using the HSEES standard names. In addition,
common synonyms for substances were added to the HSEES pick-list. Selection
of a substance synonym from the HSEES pick-list also results in mapping to an
HSEES standard name. This was done to enable HSEES staff to determine more about
specific substances reported to the HSEES system. Substance name standardization
is an ongoing project that will require periodic review of substance names not
selected from the HSEES pick-list. Each manually entered substance name will
be reviewed to determine its mapping destination. The newly established mapping
system was used to generate a list of the 100 most frequently reported substances
to the HSEES system or 1996 (Appendix A).

USE OF HSEES DATA

ATSDR continues to respond to requests for HSEES information from
local, state, and federal agencies and organizations. In addition, ATSDR continues
to receive requests from researchers from various countries and territories
for the HSEES protocol and data collection form to help develop similar surveillance
systems in their countries. The HSEES data has also been used to produce several
publications (Appendix B). The substance name standardization
project will allow greater opportunity to perform analyses on specific substances
reported to the database.

SUMMARY OF RESULTS, 1990 - 1996

The number of events, substances released, events with victims,
and deaths for the years 1990 through 1996 are shown in Table
7. In the 7 years of data collection, most events have involved a single
substance and have occurred at fixed facilities. Respiratory irritation has
consistently been reported as the most common injury experienced by victims.
In 1996, a total of 33 fatalities were reported to the system. This number represents
the largest number of deaths reported to the system during a data collection
year. The overall percentage of events involving victims, however, has declined
from 19% in 1990 to 7% in 1996. The decrease in the number of events involving
victims may be indicative of increased or strengthened procedures to protect
health and safety. However, the large number of deaths associated with events
suggests the need to evaluate not only the danger posed by exposure to hazardous
substances, but also the circumstances surrounding the occurrence of events.

Figure 4 shows the distribution
of victims for the years 1990 through 1996. Employees continue to be the most
commonly reported victims of emergency events. Cumulative data on the number
of events, substances, victims, and events involving victims are displayed in
Figure 5. Overall, the results of HSEES
data collection have remained constant, and this pattern of stability should
allow for the identification of risk factors related to the occurrence of emergency
events and the associated morbidity and mortality. Findings from HSEES data
collection efforts can provide a wealth of information for developing training
and health education programs for first responders, as well as for manufacturers
and transporters of hazardous materials.